Recently, as next-generation nonvolatile semiconductor memories, much attention has been paid to resistance change memories such as a resistive RAM (ReRAM) using a variable resistive element as a memory element, and a phase change RAM (PCRAM) using a phase change element as a memory element.
These resistance change memories are characterized in that the shrinking of each element is relatively easy and a higher memory capacity can be realized by three-dimensional integration using a cross-point memory cell array. In addition, the resistance change memories are capable of achieving the same high-speed operation as in a DRAM.
If the resistance change memory having such characteristics is put to practical use, a flash memory serving as a file memory or a DRAM serving as a work memory, for example, can be replaced with the resistance change memory. Accordingly, various configurations and operations of the resistance change memory have been suggested (e.g., see Jpn. Pat. Appln. KOKAI Publication No. 2009-99200). In order to put the resistance change memory to practical use, characteristic improvements such as high-speed operation, high reliability and low power consumption are required for the resistance change memory.